Name: SCILABURL: http://www.scilab.orgLicense: Open-source with custom license (you can't sell the program if you modify it)Platform: Windows/Linux/Solaris/Mac OS X/HP-UXAlternative to: MATLABReview: A powerful system for working with mathematics. Aims to be a free clone of MATLAB.

Name: aMSN URL:http://amsn.sf.netLicense: GPL Platform: Windows, Linux, Mac OS X. Any OS where Tcl/Tk is availableAlternative to: MSN MessengerReview: One of the most developed MSN Messenger clients. Compatible with most features of the Microsoft client.

Name: Wings 3DURL: http://www.wings3d.com/License: GPLPlatform: Windows, Linux, Mac OS XAlternative to: 3D Studio MaxReview: A powerful program to make 3D graphics. Does not do animations yet, but is easier to use than Blender.